Effect of High-Carbohydrate Diet on Lipid Metabolism in Young Type I Diabetics: Transient Changes in High-Density Lipoprotein2and Lipoprotein Lipase

The short-term effect of a high-carbohydrate, low-fat diet on lipoprotein metabolism was evaluated in eight young patients with type I diabetes mellitus. An isocaloric exchange diet containing 60% carbohydrate and 20% fat was administered for four weeks and serum lipid, high-density lipoprotein and subfraction cholesterol, and the activity of the lipolytic enzymes in postheparin plasma were monitored. The assay methods for lipase activity and cholesterol concentration in high-density lipoprotein subfractions were described previously. There were no appreciable changes in diabetic control, serum triglyceride and total cholesterol levels. The high-density lipoprotein2 cholesterol level decreased significantly after two weeks on the diet and returned toward baseline levels thereafter. There was a significant correlation between high-density lipoprotein2 cholesterol level and lipoprotein lipase activity. The high carbohydrate diet did not affect the glycemic control but induced a transient decrease in high-density lipoprotein2 cholesterol mediated by the decrease in lipoprotein lipase activity.